1. Field of the Invention
Methods and apparatuses consistent with the present invention relate to location input, and more particularly, to a method and apparatus for inputting a three-dimensional (3D) location.
2. Description of the Related Art
Due to the development of image processing technology, a two-dimensional (2D) image technology is substituted by a three-dimensional (3D) image technology. Users can watch more realistic images by realizing a 3D image according to the 3D image technology. In this regard, due to the development of the 3D image technology, there is an increasing demand for a method of inputting a 3D location.
Conventionally, in order to input the 3D location, an input apparatus transmitting an ultrasonic signal and three sensors receiving the ultrasonic signal have been used. The three sensors are used to measure 3D coordinates of an X-axis, a Y-axis, and a Z-axis. According to a location of the input apparatus, a time taken for the ultrasonic signal transmitted from the input apparatus to reach each of the three sensors differs. Each of the three sensors calculates the time taken with respect to the ultrasonic signal, and determines the 3D location desired by a user, according to a value obtained from the calculation. The determined 3D location is output to a display unit displaying a 3D image, and displayed to the user.
Another conventional method of inputting the 3D location is to use a touch screen which separately has an additional device and which is enabled to receive 2D coordinates. First, a user touches the touch screen by using a touch pen, thereby deciding the 2D coordinates. After that, the user presses the touch pen, thereby moving a cursor in a depth direction. Otherwise, an angle between the touch pen and the touch screen is measured so that the cursor is moved in a direction at which the corresponding angle can be maintained. In this case, a separate additional device capable of detecting a press force and a separate additional device capable of measuring the angle have to be installed in the touch screen.
In this manner, in order to input the 3D location by using the conventional techniques, the additional devices such as the ultrasonic sensor or the press force sensor are required, as well as a 2D location input apparatus. However, these additional devices such as the sensors are expensive, and users cannot input the 3D location unless they install the additional devices in an existing 2D input apparatus or unless they separately purchase a 3D input apparatus.